You stick ur two fingers in your own ass and then whipe it on the forehead of your partner and say "Simba" in a way similar to the scene at the beginning of lion king where rafiki whipes the fruit on simbas forehead before exposing him to the kingdom.

Matias: Dude, Mike! I just gave Jon Montgomery a Rafiki!
Mike: Dude thats nasty!
Matias: Just kidding it was to a chick
Ravi: Top Dogg!